XSL, Extensible Stylesheet Language, is a family of recommendations for defining XML document transformation and presentation. It consists of three parts:

• XSL Transformations (XSLT) - a language for transforming XML
• the XML Path Language (XPath)- an expression language used by XSLT to access or refer to parts of an XML document. (XPath is also used by the XML Linking specification)
• XSL Formatting Objects (XSL-FO) - an XML vocabulary for specifying formatting semantics

An XSLT stylesheet specifies the presentation of a class of XML documents by describing how an instance of the class is transformed into an XML document that uses a formatting vocabulary, such as (X)HTML or XSL-FO. Is is an alternate standard related to CSS. They are compared in the table below:

	CSS	XSL
Can be used with HTML?	yes	no
Can be used with XML?	yes	yes
Transformation language?	no	yes
Syntax	CSS	XML

[edit] For more information

• http://www.w3.org/Style/XSL/

• DocBook is a program that aid in XSL styleheets for XML documents.